I don't know the direct translation but this is my version of it… "You thought she's 'Maria Clara' but in reality she's 'Maria Ozawa' "…
Maria Clara is one of the characters in Jose Rizal's novel "Noli Me Tangere" (Touch Me Not) … She is a symbol of purity, modesty and fidelity.
Maria Ozawa, on the other hand, is a sex symbol — a porn star. Tee-hee~
Guys coined this saying to describe a girl who they think looks so decent, innocent or naive only to find out that she's actually an immoral woman who opens her legs to anyone.